Updated 21:00

Convicted murderer Graham Dwyer has won his legal action against the State over evidence used to prosecute him for murder. 

The former architect was convicted by a jury three years ago of the 2012 murder of childcare worker Elaine O’Hara.

He was sentenced to life in prison - however he later launched a legal action against the state and the Garda Commissioner arguing that data gathered from his phone shouldn't have been used during the trial.

The data - which placed the phone at specific places at particular times - formed a huge part of the trial.

However Dwyer argued that it shouldn’t have been used as it breached his right to privacy.

Gardaí gathered the information using laws that were brought in under a European directive. However the directive was later declared invalid by the European Court of Justice.

The High Court today ruled that Irish laws - which allow for mobile phone data to be retained and accessed - are in breach of EU law.

It means he has won this stage of his legal battle.

Dwyer, who maintains his innocence, was not in court for the ruling. He has already stated his intention to go to the Court of Appeal to challenge his murder conviction.

A date for the appeal hasn’t been set yet.

The Justice Minister, meanwhile, described today's judgement as a very detailed and lengthy one which will have to be considered very carefully to identify exactly what actions are necessary.

Reporting from Stephanie Rohan ...